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Author Gariazzo, S.; de Salas, P.F.; Pastor, S.
Title (down) Thermalisation of sterile neutrinos in the early universe in the 3+1 scheme with full mixing matrix Type Journal Article
Year 2019 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 07 Issue 7 Pages 014 - 30pp
Keywords cosmological neutrinos; neutrino properties; particle physics – cosmology connection; physics of the early universe
Abstract In the framework of a 3+1 scheme with an additional inert state, we consider the thermalisation of sterile neutrinos in the early Universe taking into account the full 4 x 4 mixing matrix. The evolution of the neutrino energy distributions is found solving the momentum-dependent kinetic equations with full diagonal collision terms, as in previous analyses of flavour neutrino decoupling in the standard case. The degree of thermalisation of the sterile state is shown in terms of the effective number of neutrinos, N-eff, and its dependence on the three additional mixing angles (theta(14), theta(24), theta(34)) and on the squared mass difference Delta m(41)(2) is discussed. Our results are relevant for fixing the contribution of a fourth light neutrino species to the cosmological energy density, whose value is very well constrained by the final Planck analysis. For the preferred region of active-sterile mixing parameters from short-baseline neutrino experiments, we find that the fourth state is fully thermalised (N-eff similar or equal to 4).
Address [Gariazzo, S.; Pastor, S.] Univ Valencia, CSIC, Inst Fis Corpuscular, Valencia, Spain, Email: gariazzo@ific.uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000474782100001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4076
Permanent link to this record
 
 
Author Plaza, J.; Martinez, T.; Becares, V.; Cano-Ott, D.; Villamarin, D.; de Rada, A.P.; Mendoza, E.; Pesudo, V.; Santorelli, R.; Pena, C.; Balibrea-Correa, J.; Boeltzig, A.
Title (down) Thermal neutron background at Laboratorio Subterraneo de Canfranc (LSC) Type Journal Article
Year 2023 Publication Astroparticle Physics Abbreviated Journal Astropart Phys.
Volume 146 Issue Pages 102793 - 9pp
Keywords Underground neutron background; Thermal neutron flux; He-3 proportional counter; Pulse shape discrimination
Abstract The thermal neutron background at Laboratorio Subterraneo de Canfranc (LSC) has been determined using several He-3 proportional counter detectors. Bare and Cd shielded counters were used in a series of long measurements. Pulse shape discrimination techniques were applied to discriminate between neutron and gamma signals as well as other intrinsic contributions. Montecarlo simulations allowed us to estimate the sensitivity of the detectors and calculate values for the background flux of thermal neutrons inside Hall-A of LSC. The obtained value is (3.5 +/- 0.8)x10(-6) n/cm(2)s, and is within an order of magnitude compared to similar facilities.
Address [Plaza, J.; Martinez, T.; Becares, V; Cano-Ott, D.; Villamarin, D.; Perez de Rada, A.; Mendoza, E.; Pesudo, V; Santorelli, R.] Ctr Invest Energet Medioambientales & Tecnol CIEM, Ave Complutense 40, Madrid 28040, Spain, Email: julio.plaza@ciemat.es
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0927-6505 ISBN Medium
Area Expedition Conference
Notes WOS:000928281600001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5482
Permanent link to this record
 
 
Author Navarro, J.; Guardiola, R.
Title (down) Thermal Effects on Small Para-Hydrogen Clusters Type Journal Article
Year 2011 Publication International Journal of Quantum Chemistry Abbreviated Journal Int. J. Quantum Chem.
Volume 111 Issue 2 Pages 463-471
Keywords atomic and molecular clusters; phase transitions in clusters; structure of clusters; molecular hydrogen and isotopes
Abstract A brief review of different quantum Monte Carlo simulations of small (p-H-2)(N) clusters is presented. The clusters are viewed as a set of N structureless p-H-2 molecules, interacting via an isotropic pairwise potential. Properties as superfluidity, magic numbers, radial structure, excitation spectra, and abundance production of (p-H-2)(N) clusters are discussed and, whenever possible, a comparison with He-4(N) droplets is presented. All together, the simulations indicate that temperature has a paradoxical effect of the properties of (p-H-2)(N) clusters, as they are solid-like at high T and liquid-like at low T, due to quantum delocalization at the lowest temperature.
Address [Navarro, Jesus; Guardiola, Rafael] Univ Valencia, CSIC, IFIC, Valencia 46071, Spain, Email: navarro@ific.uv.es
Corporate Author Thesis
Publisher John Wiley & Sons Inc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 0020-7608 ISBN Medium
Area Expedition Conference
Notes ISI:000285311400028 Approved no
Is ISI yes International Collaboration no
Call Number IFIC @ pastor @ Serial 589
Permanent link to this record
 
 
Author Vincent, A.C.; Scott, P.
Title (down) Thermal conduction by dark matter with velocity and momentum-dependent cross-sections Type Journal Article
Year 2014 Publication Journal of Cosmology and Astroparticle Physics Abbreviated Journal J. Cosmol. Astropart. Phys.
Volume 04 Issue 4 Pages 019 - 31pp
Keywords dark matter theory; stars
Abstract We use the formalism of Gould and Raffelt [1] to compute the dimensionless thermal conduction coefficients for scattering of dark matter particles with standard model nucleons via cross-sections that depend on the relative velocity or momentum exchanged between particles. Motivated by models invoked to reconcile various recent results in direct detection, we explicitly compute the conduction coefficients alpha and kappa for cross-sections that go as v(rel)(2), v(rel)(4), v(rel)(-2), q(2), q(4) and q(-2), where v(rel) is the relative DM-nucleus velocity and q is the momentum transferred in the collision. We find that a v(rel)(-2) depend ence can significantly enhance energy transport from the inner solar core to the outer core. The same can true for any q-dependent coupling, if the dark matter mass lies within some specific range for each coupling. This effect can complement direct searches for dark matter; combining these results with state-of-the-art solar simulations should greatly increase sensitivity to certain DM models. It also seems possible that the so-called Solar Abundance Problem could be resolved by enhanced energy transport in the solar core due to such velocity-or momentum-dependent scatterings.
Address [Vincent, Aaron C.] Univ Valencia, CSIC, Inst Fis Corpuscular IFIC, E-46071 Valencia, Spain, Email: vincent@ific.uv.es;
Corporate Author Thesis
Publisher Iop Publishing Ltd Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1475-7516 ISBN Medium
Area Expedition Conference
Notes WOS:000343042800001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 1962
Permanent link to this record
 
 
Author Araujo Filho, A.A.; Furtado, J.; Hassanabadi, H.; Reis, J.A.A.S.
Title (down) Thermal analysis of photon-like particles in rainbow gravity Type Journal Article
Year 2023 Publication Physics of the Dark Universe Abbreviated Journal Phys. Dark Universe
Volume 42 Issue Pages 101310 - 8pp
Keywords Rainbow gravity; Thermodynamics; Bounds
Abstract This work is devoted to study the thermodynamic behavior of photon-like particles within the rainbow gravity formalism. To to do this, we chose two particular ansatzs to accomplish our calculations. First, we consider a dispersion relation which avoids UV divergences, getting a positive effective cosmological constant. We provide numerical analysis for the thermodynamic functions of the system and bounds are estimated. Furthermore, a phase transition is also expected for this model. Second, we consider a dispersion relation employed in the context of Gamma Ray Bursts. Remarkably, for this latter case, the thermodynamic properties are calculated in an analytical manner and they turn out to depend on the harmonic series Hn, gamma & UGamma; (z), polygamma & psi;n(z) and zeta Riemann functions & zeta;(z).
Address [Araujo Filho, A. A.] Univ Valencia, CSIC, Dept Fis Teor & IFIC, Ctr Mixto Univ Valencia, Valencia 46100, Spain, Email: dilto@fisica.ufc.br;
Corporate Author Thesis
Publisher Elsevier Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN ISBN Medium
Area Expedition Conference
Notes WOS:001062674000001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5667
Permanent link to this record
 
 
Author Banerjee, P.; Carloni Calame, C.M.; Chiesa, M.; Di Vita, S.; Engel, T.; Fael, M.; Laporta, S.; Mastrolia, P.; Montagna, G.; Nicrosini, O.; Ossola, G.; Passera, M.; Piccinini, F.; Primo, A.; Ronca, J.; Signer, A.; Torres Bobadilla, W.J.; Trentadue, L.; Ulrich, Y.; Venanzoni, G.
Title (down) Theory for muon-electron scattering @ 10 ppm: A report of the MUonE theory initiative Type Journal Article
Year 2020 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 80 Issue 6 Pages 591 - 23pp
Keywords
Abstract We review the current status of the theory predictions for elastic μ-e scattering, describing the recent activities and future plans of the theory initiative related to the proposed MUonE experiment.
Address [Banerjee, P.; Engel, T.; Signer, A.; Ulrich, Y.] Paul Scherrer Inst, CH-5232 Villigen, Switzerland, Email: adrian.signer@psi.ch
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000546247100015 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4456
Permanent link to this record
 
 
Author Miyahara, K.; Hyodo, T.; Oka, M.; Nieves, J.; Oset, E.
Title (down) Theoretical study of the Xi(1620) and Xi(1690) resonances in Xi(c)-> pi(+) MB decays Type Journal Article
Year 2017 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 95 Issue 3 Pages 035212 - 12pp
Keywords
Abstract Nonleptonic weak decays of Xi(c) into pi(+) and a meson (M)-baryon (B) final state, MB, are analyzed from the viewpoint of probing S = -2 baryon resonances, i.e., Xi(1620) and Xi(1690), of which spin-parity and other properties are not well known. We argue that the weak decay of Xi(c) is dominated by a single quark-line diagram, preferred by the Cabibbo-Kobayashi-Maskawa coefficient, color recombination factor, the diquark correlation, and the kinematical condition. The decay process has an advantage of being free from meson resonances in the p+ M invariantmass distribution. The invariant mass distribution of the meson-baryon final state is calculated with three different chiral unitary approaches, assuming that the Xi(1620) and Xi(1690) resonances have J(P) = 1/2(-). It is found that a clear peak for the Xi(1690) is seen in the pi Xi and K Lambda spectra. We also suggest that the ratios of the pi Xi, K Lambda, and K Sigma final states are useful to distinguish whether the peak is originated from the Xi(1690) resonance or it is a K Sigma threshold effect.
Address [Miyahara, Kenta] Kyoto Univ, Grad Sch Sci, Dept Phys, Kyoto 6068502, Japan, Email: miyahara.kenta.62r@st.kyoto-u.ac.jp
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000399144100008 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 3044
Permanent link to this record
 
 
Author Martinez Torres, A.; Khemchandani, K.P.; Oset, E.
Title (down) Theoretical study of the gamma d -> pi(0)eta d reaction Type Journal Article
Year 2023 Publication Physical Review C Abbreviated Journal Phys. Rev. C
Volume 107 Issue 2 Pages 025202 - 24pp
Keywords
Abstract We have done a theoretical study of the gamma d -> pi(0)eta d reaction starting with a realistic model for the gamma N -> pi(0)eta N reaction that reproduces cross sections and polarization observables at low energies and involves the gamma N -> Delta(1700) -> eta Delta(1232) -> eta pi N-0 process. For the coherent reaction in the deuteron we considered the impulse approximation together with the rescattering of the pions and the eta on a different nucleon than the one where they are produced. We found this second mechanism very important since it helps share between two nucleons the otherwise large momentum transfer of the reaction. Other contributions to the gamma d -> pi(0)eta d reaction, involving the gamma N -> pi(+/-)pi N-0' process, followed by the rescattering of the pi(+/-) with another nucleon to give eta and a nucleon, have also been included. We find a natural explanation, tied to the dynamics of our model, for the shift of the eta-d mass distribution to lower invariant masses, and of the pi(0)-d mass distribution to larger invariant masses, compared to a phase space calculation. We also study theoretical uncertainties related to the large momenta of the deuteron wave function involved in the process as well as to the couplings present in the model. Striking differences are found with the experimental angular distribution and further theoretical investigations might be necessary.
Address [Torres, A. Martinez] Univ Sao Paulo, Inst Fis, BR-05389970 Sao Paulo, Brazil, Email: amartine@if.usp.br;
Corporate Author Thesis
Publisher Amer Physical Soc Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 2469-9985 ISBN Medium
Area Expedition Conference
Notes WOS:000981821500002 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 5563
Permanent link to this record
 
 
Author Toledo, G.; Ikeno, N.; Oset, E.
Title (down) Theoretical study of the D-0 -> K-pi(+)eta reaction Type Journal Article
Year 2021 Publication European Physical Journal C Abbreviated Journal Eur. Phys. J. C
Volume 81 Issue 3 Pages 268 - 11pp
Keywords
Abstract We develop a model to study the D-0 -> K-pi(+)eta weak decay, starting with the color favored external emission and Cabibbo favored mode at the quark level. A less favored internal emission decay mode is also studied as a source of small corrections. Some pairs of quarks are allowed to hadronize producing two pseudoscalar mesons, which posteriorly are allowed to interact to finally provide the K-pi(+)eta state. The chiral unitary approach is used to take into account the final state interaction of pairs of mesons, which has as a consequence the production of the kappa (K-0*(700)) and the a(0)(980) resonances, well visible in the invariant mass distributions. We also introduce the (K) over bar*(0)eta production in a phenomenological way and show that the s-wave pseudoscalar interaction together with this vector excitation mode are sufficient to provide a fair reproduction of the experimental data. The model provides the relative weight of the a(0)(980) to the kappa excitation, and their strength is clearly visible in the low energy part of the K pi spectrum.
Address [Toledo, Genaro] Univ Nacl Autonoma Mexico, Inst Fis, AP 20-364, Mexico City 01000, DF, Mexico, Email: toledo@fisica.unam.mx;
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6044 ISBN Medium
Area Expedition Conference
Notes WOS:000636246200001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 4776
Permanent link to this record
 
 
Author Sekihara, T.; Martinez Torres, A.; Jido, D.; Oset, E.
Title (down) Theoretical study of incoherent phi photoproduction on a deuteron target Type Journal Article
Year 2012 Publication European Physical Journal A Abbreviated Journal Eur. Phys. J. A
Volume 48 Issue 1 Pages 10 - 17pp
Keywords
Abstract We study the photoproduction of phi mesons in deuteron, paying attention to the modification of the cross-section from bound protons to the free ones. For this purpose we take into account Fermi motion in single scattering and rescattering of phi to account for phi absorption on a second nucleon as well as the rescattering of the proton on the neutron. We find that the contribution of the double scattering for phi is much smaller than the typical cross-section of gamma p -> phi p in free space, which implies a very small screening of the phi production in deuteron. The contribution from the proton rescattering, on the other hand, is found to be not negligible compared to the cross-section of gamma p -> phi p in free space, and leads to a moderate reduction of the phi photoproduction cross-section on a deuteron at forward angles if the LEPS set-up is taken into account. The Fermi motion allows contribution of the single scattering in regions forbidden by phase-space in the free case. In particular, we find that for momentum transfer squared close to the maximum value, the Fermi motion changes drastically the shape of d sigma/dt, to the point that the ratio of this cross-section to the free one becomes very sensitive to the precise value of t chosen, or the size of the bin used in an experimental analysis. Hence, this particular region of t does not seem to be the most indicated to find effects of a possible phi absorption in the deuteron. This reaction is studied theoretically as a function of t and the results are contrasted with recent experiments at LEPS and Jefferson Lab. The effect of the experimental angular cuts at LEPS is also discussed, providing guidelines for future experimental analyses of the reaction.
Address [Sekihara, T.] Kyoto Univ, Grad Sch Sci, Dept Phys, Kyoto 6068502, Japan, Email: sekihara@th.phys.titech.ac.jp
Corporate Author Thesis
Publisher Springer Place of Publication Editor
Language English Summary Language Original Title
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN 1434-6001 ISBN Medium
Area Expedition Conference
Notes WOS:000300285400001 Approved no
Is ISI yes International Collaboration yes
Call Number IFIC @ pastor @ Serial 912
Permanent link to this record